Which measurement occurs last when collecting data to determine the percentage by mass of a solution?

mass percent = (mass of element in 1 mole of compound / mass of 1 mole of compound) x 100. The formula for a solution is:

mass percent = (grams of solute / grams of solute plus solvent) x 100. or.

mass percent = (grams of solute / grams of solution) x 100. The final answer is given as %.

Hope this helps!!

i'm assuming that it's c.) red bank..

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

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since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.